Generally, a glow plug is a device for preheating a combustion chamber of a diesel engine.
In the diesel engine, since an ignition of fuel due to a compression heat of air occurs, when suddenly turning on an electric motor, the electric motor is not started. Therefore, after an inside of the combustion chamber is preheated to 800° C. or above by applying an electric current to the glow plug, the fuel is injected to perform an ignition of the engine and a starting of the electric motor. After operating a preheating switch before starting the electric motor, it is common that a driver confirms =that the preheating is completed when a warning lamp is turned off.
Recently, it became possible to instantaneously raise temperature of the combustion chamber with a metal glow device. However, in order to improve a fuel consumption rate and reduce harmful material of an exhaust gas, it may be difficult to avoid an interference between the glow plug protruded to the combustion chamber and the fuel due to an injection area increasing of the fuel in the combustion chamber through an injector multicomponent, etc.
The above information disclosed in this section is only for enhancement of understanding of the background of the disclosure and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.